Ultrasound Imaging Probe

ABSTRACT

An elongate ultrasound probe including a probe head with a transducer array, a handle, a flexor located between and affixed to the probe head and the handle, a flexor actuator configured to flex the flexor, and a probe head motion actuator configured to oscillate the flexor actuator and thereby oscillate the probe head. A method includes electronically vibrating a probe head, which includes a transducer array, of an ultrasound probe in connection with ultrasound elasticity imaging.

TECHNICAL FIELD

The following generally relates to ultrasound and more particularly toan ultrasound probe and is described with particular application toultrasound imaging; however, the probe can be employed with otherultrasound applications.

BACKGROUND

Ultrasound (US) imaging has provided useful information about theinterior characteristics of an object or subject under examination. A USimaging system has included an ultrasound probe housing a transducerarray that is configured to transmit an ultrasound signal into a scanfield of view and receive echoes produced in response to the ultrasoundsignal interacting with structure of an object or subject therein. Asthe ultrasound signal traverses the object or subject, portions of theultrasound signal are attenuated, scattered, and/or reflected offstructure and/or boundaries in the interior of the object or subject,with some of the reflections traversing back towards the transducerarray. The later reflections (or echoes) are received at the transducerarray. In B-mode imaging, the echoes correspond to an axial slicethrough the object or subject and are processed to generate scanlines,which are used to produce a scanplane, or a two or a three dimensionalimage of the slice or volume, which are displayed via a display monitor.

Laparoscopic ultrasound examinations have been used to detect tumors incavities. Generally, there are two types of ultrasound imagingprobes—flexible and rigid. Flexible ultrasound probes include anarticulating portion that can be controllably articulated to move an endof the probe with a transducer array through an angle of up to ninety(90) degrees in one to four planes. FIGS. 1A and 1B show an example of aflexible probe 100; namely, a laparoscopic transducer type 8666, whichis a product of BK-Medical ApS, a company of Herlev, Denmark, which is awholly owned subsidiary of Analogic Corporation, a company of MA, USA.As shown in FIG. 1A, the probe 100 is configured to articulate between azero position 102 and an up position 104 and a down position 106. Asshown in FIG. 1B, the probe 100 is configured to articulate between thezero position 102 and a left position 108 and a right position 110. Incontrast, rigid probes are not configured to articulate as such andremain at the zero position 102. A lab probe can also be rigid in onedirection, or only have motion in one plane. Furthermore this can becombined with a rotational motion of the array (i.e., can be combinedwith all the above).

An indicator used to guide biopsies has been the stiffness of thetissue, as unhealthy tissue is often stiffer than surrounding healthytissue. Tissue stiffness has been determined with ultrasound using atechnique referred to as elasticity imaging. With elasticity imaging, amechanical compression (e.g., via vibration) is applied to tissue, withthe unhealthy tissue compressing less than the surrounding tissue sincethe strain is less than the surrounding tissue. The mechanicalcompression has been applied by having the user of the probe push theprobe against tissue of interest in a fluctuating manner to compress(e.g., 1 mm or so) and decompress the tissue. The measured stiffness hasbeen overplayed on top of the B-mode image. With laparoscopic imaging,there is no direct visibility of the probe and the tissue, except whenused with a camera, thus making it difficult to apply suitable manualcompression to the tissue. Furthermore, since flexible probes by naturecan be twisted and rotated, it may be difficult to manually apply therequisite force in the right direction and in a stable recurrent manner.Moreover, the length of the transducer may make it difficult to manuallyapply the oscillating pressure at the tip of the probe.

SUMMARY

Aspects of the application address the above matters, and others.

In one aspect, an elongate ultrasound probe including a probe head witha transducer array, a handle, a flexor located between and affixed tothe probe head and the handle, a flexor actuator configured to flex theflexor, and a probe head motion actuator configured to oscillate theflexor actuator and thereby oscillate the probe head.

In another aspect, a method includes electronically vibrating a probehead, which includes a transducer array, of an ultrasound probe inconnection with ultrasound elasticity imaging.

In another aspect, an ultrasound imaging system includes an elongateultrasound probe. The probe includes a probe head with a transducerarray, a handle, a flexor located between and affixed to the probe headand the handle, and a flexor actuator configured to flex the flexor. Theprobe further includes a probe head motion actuator configured tooscillate the flexor actuator and thereby oscillate the probe head, andelectronics, internal to the handle, that controls at least the probehead motion actuator.

Those skilled in the art will recognize still other aspects of thepresent application upon reading and understanding the attacheddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

The application is illustrated by way of example and not limitation inthe figures of the accompanying drawings, in which like referencesindicate similar elements and in which:

FIGS. 1A and 1B illustrate a prior art laparoscopic ultrasound imagingprobe with a flexible tip;

FIG. 2 schematically illustrates an example ultrasound imaging systemincluding an ultrasound imaging probe with a probe head motion actuatorthat oscillates a probe head and a transducer array housed therein.

FIGS. 3A, 3B and 3C schematically illustrate a prior art flexor andflexor actuator configuration.

FIG. 4 schematically illustrates an example of the motion actuator.

FIGS. 5A and 5B schematically illustrate another example of the motionactuator.

FIGS. 6A and 6B schematically illustrate another example of the motionactuator.

FIGS. 7A and 7B schematically illustrate another example of the motionactuator.

FIGS. 8A and 8B illustrate another example of the motion actuator.

FIG. 9 illustrates an example method in accordance with the embodimentsherein.

DETAILED DESCRIPTION

The following describes an ultrasound probe configured for at leastlaparoscopic elasticity imaging. Initially referring FIG. 2, an imagingsystem 202 such as ultrasound imaging system is schematicallyillustrated. The imaging system 202 includes an ultrasound probe 204 anda console 206. The probe 204 includes a handle 208, a shaft 210, anarticulating member 212 and a probe head 214.

The probe head 214 includes a transducer array 216, which includes one,two or three dimensional array transducer elements. Suitableconfigurations include, but are not limited to, linear, curved (e.g.,convex), phased and matrix arrays. The transducer array 216 can be usedto acquire data for A-mode, B-mode, etc. acquisitions, individually andin combination with color flow, Doppler flow, etc.

The shaft 210 extends along a longitudinal axis 211 of the probe 204 andis geometrically configured to allow for moving and/or positioning theprobe head 214 (and thus the transducer array 216 attached thereto)within a cavity, such as the abdomen or other cavity of a human patient,or a cavity of an object.

The articulating member 212 is a generally flexible section of the probe204. A first side 218 of the articulating member 212 is affixed to theprobe head 214 and an opposing side 220 of the articulating member 212is affixed to the shaft 210.

A flexor 222 is controlled to flex the articulating member 212 toposition the transducer array 216 between various positions in one tofour planes through angles of up to one hundred and seventy (170)degrees and/or straight (zero degrees) along the longitudinal axis 211of the probe 204. Examples of positions include those shown inconnection with FIGS. 1A and 1B.

The handle 208 includes a flexor actuator 224, a probe head motionactuator 226, and electronics 228.

The flexor actuator 224 is configured to actuate the flexor 222 to movethe head 214 and thus the transducer array 216 through the variousangels discussed herein. Various approaches can be utilized to actuatethe flexor 222. An example of a suitable manual approach is discussed inFIGS. 3A, 3B and 3C and used in connection with the laparoscopictransducer type 8666. In an alternative embodiment, the electronics 228include circuitry for electronically controlling the flexor 222.

The probe head motion actuator 226 is configured to translate the flexor222 and hence the probe head 214 and transducer array 216, e.g., whenthe system 202 is operated in elasticity imaging mode, e.g., inconnection with a laparoscopic or other procedure. As described ingreater detail below, the probe head motion actuator 226 is incorporatedwith and controllably oscillates (or vibrates) the flexor actuator 224in the handle 208, which oscillates the probe head 214 and transducerarray 216. Such oscillating is well-suited for applying mechanicalcompression or vibration to tissue for elasticity imaging.

The probe head motion actuator 226 can be controlled internally, forexample, by the electronics 228 and/or by an external device. Witheither instance, the user and/or other personnel need only activate themotion actuator 226 to oscillate the transducer array 216, mitigatinghaving to have the user manually push the probe head 214 against tissueof interest in a fluctuating manner to compress and decompress thetissue. This electronically controlled oscillation also facilitatesapplying suitable force at a suitable frequency in cavities with low tono visibility, such as with laparoscopic procedures. Examples ofsuitable frequencies are frequencies that will compress the tissue ofinterest up to two millimeters, such as 0.5 to 5.0 Hz.

The electronics 228 are in electrical communication with the ultrasoundtransducer array 216 and are used to convey signals to the ultrasoundtransducer array 216 that actuate the individual transducer elementstherein to produce ultrasound signals and receive signals therefromcorresponding to received echoes. Alternatively, the electronics 228 canreside outside of the ultrasound probe 204, for example, in connectionwith console 206 and/or elsewhere.

It is to be appreciated that the probe 204 can be used for laparoscopic,endoscopic, and/or other ultrasound applications, and can be used toassist personnel, for example, with an interventional procedure such asa liver, gall bladder, tumor biopsy, etc., guide personnel, for example,with RF ablation, chemical injection, etc. As shown, the probe 204 isemployed with the console 206. In other embodiments, the probe 204 canbe employed with other consoles and/or device, via cable or wirelesscommunication.

The console 206 includes a transmit circuit 232 that controls thephasing and/or time of actuation of the individual elements of thetransducer array 216, which allows for steering and/or focusing thetransmitted beam from predetermined origins along the array and atpredetermined angles.

The console 206 further includes a receive circuit 234 that receivessignals indicative of the echoes received by the transducer array 216.For B-mode and/or other applications, the receive circuit 234 canbeamform (e.g., delays and sums) the echoes into a sequence of focused,coherent echo samples along focused scanlines of a scanplane. Forelastography imaging, the echoes include tissue motion or displacementinformation between the frames of data.

A controller 236 controls the transmit circuit 232 and/or the receivecircuit 234. Such control may include, but is not limited to,controlling the frame rate, number of scanline groups, transmit angles,transmit energies, transmit frequencies, transmit and/or receive delays,etc., and/or activating the motion actuator 226 for elasticity imaging.

An echo processor 244 processes received echoes. Such processingincludes beamforming (e.g., delay and sum) the echoes in connection withB-mode imaging, etc. A motion processor 246 extracts and processes thetissue motion information from the echoes in connection withelastography imaging. Other processing lowers speckle, improves specularreflector delineation, and/or includes FIR filtering, IIR filtering,etc.

A scan converter 238 scan converts the frames of data to generate datafor display, for example, by converting the data to the coordinatesystem of the display. This may include changing the vertical and/orhorizontal scan frequency of signal based on the display. Furthermore,the scan converter 238 can be configured to employ analog and/or digitalscan converting techniques.

A rendering engine 248 is configured to at least generate elastographyor other images based on the processed data. The elastography images canbe visually presented, stored, conveyed to another device, and/orotherwise utilized. A display 240 presents the rendered data.

A user interface 242 includes input and/or output devices forinteracting with the controller 236, e.g., to select a data processingand presentation mode, a data acquisition mode (e.g., B-mode, elasticityimaging, etc.), initiate scanning, etc. The user interface 242 mayinclude controls such as buttons, knobs, a keypad, a touch screen, etc.The user interface 242 may also include visual (e.g., LCD, LED, etc.)and/or audible displays.

In the illustrated embodiment, the probe 204 and the console 206respectively include complementary electrical interfaces, which can beelectrically connected via a cable, wireless communication, or the like.The electrical connection there between allows electrical signals to beconveyed back and forth between the probe 204 and the console 206.

It is to be understood that the relative size, shape and position of thevarious components of the system 202 are provided for explanatorypurposes and are not limiting. In other embodiments, at least one of thesize, shape and position of at least one of the components is different.

FIGS. 3A, 3B and 3C schematically illustrate an example of prior artconfiguration of the flexor actuator 224 in connection with the handle208, the shaft 210, the flexor 222, and the probe head 214.

The flexor actuator 224 includes a cable 302. An end 304 of the cable302 is affixed to a first portion 306 of the flexor 222. The flexoractuator 224 further includes a cable 308. An end 310 of the cable 308is affixed to a second or opposing portion 312 (which opposes portion306) of the flexor 222.

Opposing ends 314 and 316 of the cables 302 and 308 are affixed to amovable member 318, with the end 314 of the cable 302 affixed to a firstregion 320 of the movable member 318 and the end 316 of the cable 308affixed to second region 322 (which opposes the region 320) of themovable member 318.

A shaft 328 is affixed to the movable member 318 and is configured tomove the movable member 318. In the illustrated embodiment, the movablemember 318 is circular in shape and is affixed to rotate through apredetermined angle range or arc 324 about a rotational axis 326, theshaft 328 is affixed at the rotational axis 326, and moving the shaft328 through range of the arc 324 rotates the moveable member 318 aboutthe rotational axis 326.

In this configuration, pivoting the shaft 328 away from the probe head214 concurrently urges the second cable 308 in a direction towards theprobe head 214 and pulls the first cable 302 in a direction away fromthe probe head 214. As a result, the flexor 222 is flexed such that thefirst portion 306 flexes away from the axis 211 and the second portion312 flexes towards the axis 211. This is shown in FIG. 3B.

Furthermore, pivoting the shaft 328 towards the probe head 214concurrently urges the first cable 302 in a direction towards the probehead 214 and pulls the second cable 308 in a direction away from theprobe head 214. As a result, the flexor 222 is flexed such that thefirst portion 306 flexes towards the axis 211 and the second portion 312flexes away from the axis 211. This is shown in FIG. 3C.

Where the cables 302 and 308 are for up/down motion, pivoting the shaft328 as described herein flexes the probe head 214 up and down. Where thecables 302 and 308 are for left/right motion, pivoting the shaft 328 asdescribed herein flexes the probe head 214 left and right. Although onlya pair of cables 302 and 308 is shown for up/down or left/right motion,it is to be understood that there are at least two such pairs, one pairfor up/down motion and another pair for left/right motion.

When the shaft 328 is pivoted to a generally central position of the arc324, the tension on the cables 302 and 308 is approximately equal, andthe probe heads 214 extends axially along the axis 211. It is to beappreciated that location and/or length of the arc 324 is not limiting.In addition, the shaft 328 could be located on the opposing side and/orotherwise shaped.

Furthermore, the moveable member 318 could instead be a slide mechanism,including two sliding members that linearly slide in opposing direction.In this manner, translating the moveable member 318 towards and awayfrom the probe head 214 has a same effect as discussed above withrespect to flexing the probe head 214.

Turning now to FIG. 4, a first example of the motion actuator 226 isillustrated. In this example, the motion actuator 226 includes anelectro-mechanical device 400 with two guides 402 and 404 located in ahousing 406 and configured to roll therein. In one instance, one or moreof the guides 402 and 404 rotates about a pin 408 (as shown). In anotherinstance, the guides 402 and 404 are free floating within the housing.

As shown, the cable 302 is sandwiched between and physically contactsthe guides 402 and 404. Where the guides 402 and 404 rotate, the guides402 and 404 are set separated from each other so that the cable 302 canbe fed there between. Where the guides 402 and 404 free floating, theguides 402 and 404 will move when installing the cable 302.

When pivoting the shaft 328 as discussed above, for example, towards andaway from the probe head 214, the guides 402 and 404 remain at a staticlocation, but the guides 402 and 404 roll as the cable 302 translatesthere between towards and away from the probe head 214.

A control portion 410, in response to an activation signal,automatically and electronically causes the guides 402 and 404 tooscillate, which causes the cable 302 to oscillate (translate back andforth, vibrate, etc.). The control portion 410 controllably oscillatesthe guides 402 and 404, for example, at a frequency suitable forelasticity imaging. The control portion 410 may include a device such asa piezoelectric vibration generator or the like.

The electro-mechanical device 400 can be activated via a button, knob,slider, etc. located on the probe 204. Additionally or alternatively,the electro-mechanical device 400 can be activated via the console 206.Additionally or alternatively, the electro-mechanical device 400 can beactivated via a remote control. Additionally or alternatively, theelectro-mechanical device 400 can be activated via other device.

FIGS. 5A and 5B show another example of the motion actuator 226.

In this example, the motion actuator 226 includes a guide 502. The guide502 is generally elliptical in shape, located at a fixed position, andconfigured to rotate about a pin 504. The guide 502 is located such thatthe guide 502 contacts the cable 302 at least when its long axis isperpendicular to the cable 302 (FIG. 5B). In this manner, rotating theguide 502 will vary the force on the cable 302 as a function of rotationangle as the guide 502 rotates, creating an oscillation.

The illustrated elliptical shape is not limiting. Generally, the member502 can be any shape that will produce a varying force against the cable302 while rotating the member 502, oscillating the cable 302. Examplesof other shapes include triangular, rectangular, irregular, etc. Morethan one member 502 can be used can be used with the cable 302 and/or308.

FIGS. 6A and 6B show another example of the motion actuator 226.

In this example, the motion actuator 226 includes a guide 602, which isin physical contact with the cable 302. An expandable/contractiblechamber 604 is located adjacent to the guide 602. The chamber 604 ispositioned such that when no fluid (e.g., air, gas, liquid, gel, etc.)is introduced into the chamber, either no or a minimum amount of forceis exerted on the cable 302.

A fluid mover 606 moves a fluid (e.g., a liquid or gas) into and out ofthe chamber 604 via a pathway 608. The fluid mover 606 may include amanual or electric pump or the like which supplies and draws the fluid.The illustrated mover 606 is external. However, the mover 606 canalternatively be located in the probe 204. Similar to the mechanismsdiscussed above, the fluid mover 606 moves the cable 302 so as to applya vibration to the cable 302 and have the probe head 214.

Optionally, the chamber 604 includes an egress port, which additionallyor alternatively allows removal of the fluid from the chamber 604. FIG.6A shows an empty chamber 604 and FIG. 6B shows a filled chamber 604.

FIGS. 7A and 7B show another example of the motion actuator 226.

With this example, a pushbutton including slidable element 702 that isslideably coupled within a track 704 and affixed to a guide 706. In anon-pressed state (FIG. 7A), the pushbutton 700 exerts minimal (withrespect to the force the guide 706 can exert on the cable 302) or noforce on the cable. In a fully pressed state (FIG. 7B), the pushbutton700 exerts a maximal (with respect to the force the guide 706 can exerton the cable 302) force on the cable 302.

During transition states between FIGS. 7A and 7B, the force applied bythe guide 706 fluctuates or varies as a function of the relativeposition of the slidable element 702 in the track 704. Likewise, theslidable element 702 can be operated to move the cable 302 so as toapply a vibration to the cable 302 and have the probe head 214.

FIGS. 8A and 8B show another example of the motion actuator 226. In thisexample, a rotating motor 802 drives a rod 804 that is connected via ajoint 806 such as a ball-joint or the like to a rocker arm 808 thatconverts the rotating movement into up/down movements via pivoting therocker arm 808 about a pivot 810, which oscillates the at least onecable.

FIG. 9 illustrates a method for employing the probe 204 in connectionwith elasticity imaging.

It is to be appreciated that the order of the following acts is providedfor explanatory purposes and is not limiting. As such, one or more ofthe following acts may occur in a different order. Furthermore, one ormore of the following acts may be omitted and/or one or more additionalacts may be added.

At 902, the probe 204 is inserted into a cavity of a subject or object.

At 904, the transducer array 216 is activated to emit ultrasound signalsthat traverse a field of view and an object or subject therein.

At 906, the probe head motion activator 226 is activated to vibrate theprobe head 214. As discussed herein, the vibrating probe head causes acontrolled fluctuating compression of the tissue.

At 908, the transducer array 216 is activated to emit receive echoesproduced in response to interaction with the object or subject.

At 910, the console 206 processes the echoes, creating at leastelasticity imaging information.

At 912, optionally, the console 206 visually displays the elasticityimaging information. In one instance, this may include visuallydisplaying a B or other mode image with the elasticity imaginginformation superimpose or overlayed thereon.

The above may be implemented by way of computer readable instructions,encoded or embedded on computer readable storage medium such as physicalmemory or other non-transitory medium, which, when executed by acomputer processor(s), cause the processor(s) to carry out the describedacts. Additionally or alternatively, at least one of the computerreadable instructions is carried by a signal, carrier wave or othertransitory medium.

The application has been described with reference to variousembodiments. Modifications and alterations will occur to others uponreading the application. It is intended that the invention be construedas including all such modifications and alterations, including insofaras they come within the scope of the appended claims and the equivalentsthereof.

What is claimed is:
 1. An elongate ultrasound probe, comprising: a probehead with a transducer array; a handle; a flexor located between andaffixed to the probe head and the handle; a flexor actuator configuredto flex the flexor; and a probe head motion actuator configured tooscillate the flexor actuator and thereby oscillate the probe head. 2.The probe of claim 1, wherein probe head motion actuator oscillate theflexor actuator to oscillate the probe head at a frequency forultrasound elasticity imaging.
 3. The probe of any of claim 1, theflexor actuator, comprising: at least one cable affixed to at least oneside of the flexor, wherein the probe head motion actuator oscillatesthe at least one cable, which oscillates the cable, oscillating theprobe head.
 4. The probe of claim 3, the probe head motion actuator,comprising: first and second guides which support and are in physicalcontact with the at least one cable there between; and a control portionthat oscillates the first and second guides, which oscillates the atleast one cable.
 5. The probe of claim 4, wherein oscillating the firstand second guides fluctuates an amount of force applied to the at leastone cable by the first and second guides.
 6. The probe of any of claim4, wherein the control portion is activated by at least one of theprobe, an ultrasound console, or a remote device.
 7. The probe of any ofclaim 4, wherein the control portion is electronically controlled. 8.The probe of claim 3, the probe head motion actuator, comprising: arotating guide having at least two different length axes, whereinrotating the rotating element fluctuates an amount of force applied bythe rotating guide to the at least one cable, thereby oscillating the atleast one cable.
 9. The probe of claim 3, the probe head motionactuator, comprising: a motor; a rod; a joint; and a rocker arm, whereinthe motor rotates the rod, which is connected to the joint, whichactuates the rocker arm, thereby converting the rotating movement intoan up/down movement, which oscillates the at least one cable.
 10. Theprobe of claim 3, the probe head motion actuator, comprising: a guide; achamber, wherein the chamber supports the guide in physical contact withthe at least one cable; a fluid mover that supplies a fluid to thechamber and removes the fluid from the chamber, which causes the chamberto expand and contract, varying an amount of force applied to the atleast one cable by the guide, thereby oscillating the at least onecable.
 11. The probe of claim 10, wherein the fluid mover is external tothe probe
 12. The probe of claim 8, wherein the fluid mover iselectronically controlled.
 13. The probe of claim 3, the probe headmotion actuator, comprising: a guide; a slideable element, wherein theslideable member supports the guide in physical contact with the atleast one cable; wherein depressing and releasing the slideable membercauses the guide to varying an amount of force applied to the at leastone cable by the guide, thereby oscillating the at least one cable. 14.A method, comprising: electronically vibrating a probe head, whichincludes a transducer array, of an ultrasound probe in connection withultrasound elasticity imaging.
 15. The method of claim 14, wherein theultrasound probe includes an articulating probe head in which two cablesare utilized to flex the probe head, and further comprising: moving, inresponse to the signal, at least one guide such that the at least oneguide varies an amount of force applied to at least one of the twocable, thereby oscillating the at least one cable, which oscillates theprobe head.
 16. The method of claim 15, wherein the at least one guideincludes two guides which support and are in physical contact with theat least one of the two cables there between; and further comprising:oscillating the two guides, which oscillates the at least one of the twocables.
 17. The method of claim 15, wherein the at least one guideincludes a rotating guide having at least two different length axes, andfurther comprising: rotating the rotating guide which fluctuates anamount of force applied by the rotating guide to the at least one of thetwo cables, which oscillates the at least one of the two cables.
 18. Themethod of claim 15, wherein the at least one guide is supported by anexpandable and contractible chamber, and further comprising: expandingand contracting the chamber which causes the chamber to vary an amountof force applied by the at least one guide to the at least one of thetwo cables.
 19. The method of claim 15, wherein the at least one guideis part of a manual pushbutton, depressing and releasing the pushbuttoncauses the guide to vary an amount of force applied by the at least oneguide to the at least one of the two cables.
 20. An ultrasound imagingsystem, comprising: an elongate ultrasound probe, including: a probehead with a transducer array; a handle; a flexor located between andaffixed to the probe head and the handle; a flexor actuator configuredto flex the flexor; a probe head motion actuator configured to oscillatethe flexor actuator and thereby oscillate the probe head; andelectronics, internal to the handle, that controls at least the probehead motion actuator.